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Mental health disorders are among the leading worldwide causes of disease and long-term disability. This issue has a long and painful history of gradual de-stigmatization of patients, coinciding with humanization of therapeutic approaches. What are the current trends in Russia regarding this issue and in what ways is it similar to and different from Western countries? IQ.HSE provides an overview of this problem based on research carried out by Svetlana Kolpakova.

On September 5, Laurie Manchester, Associate Professor of History at Arizona State University, presented her paper on voluntary repatriation of Russians from China to the Soviet Union between 1935 and 1960. The presentation was part of the research seminar, ‘Boundaries of History’, held regularly by the Department of History at HSE University in St. Petersburg. HSE News Service spoke with Laurie Manchester about her research interests, collaborating with HSE faculty members, and the latest workshop.

Dr. Sabyasachi Tripathi, from Kolkata, India, is a new research fellow at HSE University. He will be working at the Laboratory for Science and Technology Studies of the Institute for Statistical Studies and Economics of Knowledge.

We describe new families of the Knizhnik-Zamolodchikov-Bernard (KZB) equations related to the WZW-theory corresponding to the adjoint G-bundles of different topological types over complex curves Sigma(g,n) of genus g with n marked points. The bundles are defined by their characteristic classes - elements of H-2 (Sigma(g,n), Z(G)), where Z (G) is a center of the simple complex Lie group G. The KZB equations are the horizontality condition for the projectively flat connection (the KZB connection) defined on the bundle of conformal blocks over the moduli space of curves. The space of conformal blocks has been known to be decomposed into a few sectors corresponding to the characteristic classes of the underlying bundles. The KZB connection preserves these sectors. In this paper we construct the connection explicitly for elliptic curves with marked points and prove its flatness.

This proceedings publication is a compilation of selected contributions from the “Third International Conference on the Dynamics of Information Systems” which took place at the University of Florida, Gainesville, February 16–18, 2011. The purpose of this conference was to bring together scientists and engineers from industry, government, and academia in order to exchange new discoveries and results in a broad range of topics relevant to the theory and practice of dynamics of information systems. Dynamics of Information Systems: Mathematical Foundation presents state-of-the art research and is intended for graduate students and researchers interested in some of the most recent discoveries in information theory and dynamical systems. Scientists in other disciplines may also benefit from the applications of new developments to their own area of study.

A model for organizing cargo transportation between two node stations connected by a railway line which contains a certain number of intermediate stations is considered. The movement of cargo is in one direction. Such a situation may occur, for example, if one of the node stations is located in a region which produce raw material for manufacturing industry located in another region, and there is another node station. The organization of freight traﬃc is performed by means of a number of technologies. These technologies determine the rules for taking on cargo at the initial node station, the rules of interaction between neighboring stations, as well as the rule of distribution of cargo to the ﬁnal node stations. The process of cargo transportation is followed by the set rule of control. For such a model, one must determine possible modes of cargo transportation and describe their properties. This model is described by a ﬁnite-dimensional system of diﬀerential equations with nonlocal linear restrictions. The class of the solution satisfying nonlocal linear restrictions is extremely narrow. It results in the need for the “correct” extension of solutions of a system of diﬀerential equations to a class of quasi-solutions having the distinctive feature of gaps in a countable number of points. It was possible numerically using the Runge–Kutta method of the fourth order to build these quasi-solutions and determine their rate of growth. Let us note that in the technical plan the main complexity consisted in obtaining quasi-solutions satisfying the nonlocal linear restrictions. Furthermore, we investigated the dependence of quasi-solutions and, in particular, sizes of gaps (jumps) of solutions on a number of parameters of the model characterizing a rule of control, technologies for transportation of cargo and intensity of giving of cargo on a node station.

According to a recent paper \cite{bopt13}, polynomials from the closure $\ol{\phd}_3$ of the {\em Principal Hyperbolic Domain} ${\rm PHD}_3$ of the cubic connectedness locus have a few specific properties. The family $\cu$ of all polynomials with these properties is called the \emph{Main Cubioid}. In this paper we describe the set $\cu^c$ of laminations which can be associated to polynomials from $\cu$.

In this article we prove in a new way that a generic polynomial vector field in ℂ² possesses countably many homologically independent limit cycles. The new proof needs no estimates on integrals, provides thinner exceptional set for quadratic vector fields, and provides limit cycles that stay in a bounded domain.

Let k be a field of characteristic zero, let G be a connected reductive algebraic group
over k and let g be its Lie algebra. Let k(G), respectively, k(g), be the field of k-
rational functions on G, respectively, g. The conjugation action of G on itself induces
the adjoint action of G on g. We investigate the question whether or not the field
extensions k(G)/k(G)^G and k(g)/k(g)^G are purely transcendental. We show that the
answer is the same for k(G)/k(G)^G and k(g)/k(g)^G, and reduce the problem to the
case where G is simple. For simple groups we show that the answer is positive if G is
split of type A_n or C_n, and negative for groups of other types, except possibly G_2. A
key ingredient in the proof of the negative result is a recent formula for the unramified
Brauer group of a homogeneous space with connected stabilizers. As a byproduct of
our investigation we give an affirmative answer to a question of Grothendieck about the
existence of a rational section of the categorical quotient morphism for the conjugating
action of G on itself.

We obtain a partial solution of the problem on the growth of the norms of exponential functions with a continuous phase in the Wiener algebra. The problem was posed by J.-P. Kahane at the International Congress of Mathematicians in Stockholm in 1962. He conjectured that (for a nonlinear phase) one can not achieve the growth slower than the logarithm of the frequency. Though the conjecture is still not confirmed, the author obtained first nontrivial results.

We give an explicit formula for a quasi-isomorphism between the operads Hycomm (the homology of the moduli space of stable genus 0 curves) and BV/Δ (the homotopy quotient of Batalin-Vilkovisky operad by the BV-operator). In other words we derive an equivalence of Hycomm-algebras and BV-algebras enhanced with a homotopy that trivializes the BV-operator. These formulas are given in terms of the Givental graphs, and are proved in two different ways. One proof uses the Givental group action, and the other proof goes through a chain of explicit formulas on resolutions of Hycomm and BV. The second approach gives, in particular, a homological explanation of the Givental group action on Hycomm-algebras.

Let G be a connected semisimple algebraic group over an algebraically closed field k. In 1965 Steinberg proved that if G is simply connected, then in G there exists a
closed irreducible cross-section of the set of closures of regular conjugacy classes. We prove
that in arbitrary G such a cross-section exists if and only if the universal covering isogeny
Ĝ → G is bijective; this answers Grothendieck's question cited in the epigraph. In
particular, for char k = 0, the converse to Steinberg's theorem holds. The existence of a
cross-section in G implies, at least for char k = 0, that the algebra k[G]G of class functions
on G is generated by rk G elements. We describe, for arbitrary G, a minimal generating
set of k[G]G and that of the representation ring of G and answer two Grothendieck's
questions on constructing generating sets of k[G]G. We prove the existence of a rational
(i.e., local) section of the quotient morphism for arbitrary G and the existence of a rational
cross-section in G (for char k = 0, this has been proved earlier); this answers the other
question cited in the epigraph. We also prove that the existence of a rational section
is equivalent to the existence of a rational W-equivariant map T- - - >G/T where T is a
maximal torus of G and W the Weyl group.